transfer music FROM iPhone TO computer

I would like to transfer music FROM my iPhone TO my work computer. I cannot for the life of me determine how to do this.

The music is not on my work computer (which is why I'd like to copy it to my computer), therefore it is not shown in the main iTunes Library on this computer. That's fine & expected. The music is listed within iTunes as a song on my iPhone. Again, great. Now... how do I get these songs FROM my iPhone TO my computer? [Yes, the music I'm trying to transfer is on my home computer & listed in the iTunes there. No, I have no intention of enabling home share. Yes, I could transfer the files from my home computer onto a USB and then onto my work computer... but I SHOULDN'T HAVE TO]

The sync option only seems to work in one direction. It wants to delete ALL music from my phone and "restore" with the music from the computer. As my phone has more songs than my computer, that is obviously an issue, nor will it accomplish the goal of getting these few albums onto my computer. At this point, I'd be fine with deleting all songs off the computer & "restoring" from the phone.

As you can see below, the only option is to sync the entire music library (in the wrong direction), as the alternative options are grayed out.

[PRETEND YOU CAN SEE THE SCREENSHOT THAT I WOULD HAVE POSTED IF APPLE WOULD ALLOW ME TO ACTUALLY POST THIS FROM A COMPUTER WITHOUT TELLING ME MY SESSION HAS EXPIRED IN LESS THAN 1 MINUTE]

I've set my preferences to "show list view checkboxes" ... which does nothing to help. There are check marks next to the songs in the main iTunes library that can be unchecked... one at a time (really??), but the check marks in the device section are grayed out.

What am I not doing correctly? I know you were once able to do this.